N4L Power Analyzers utilize the latest signal processing technology. Providing fast, accurate and repeatable measurements in the most demanding of applications. Whether you need to measure the efficiency of a variable speed motor drive or the losses in a transformer, N4L have a power analyzer measurement solution for you. Combining years of experience in high frequency measurement instrumentation with innovative developments in analog and digital design techniques to produce a new generation of class leading precision power analyzer. All Power Analyzers from N4L feature real-time no gap analysis as well as high sampling rates throughout all fundamental frequencies facilitating wide band gapless measurements on any input waveform. All Power Analyzers are provided with a UKAS ISO17025 calibration certificate, issued by our internal UKAS Laboratory (Calibration Laboratory No. 7949).

What is a Power Analyzer?

A Power Analyzer is a precision test instrument that measures the power consumption or generation (in Watts) of a device, circuit or sub system. Modern Power Analyzers are also able to determine the power factor, harmonic distortion, peak, mean and many more parameters of a signal.

A Power Analyzer samples the voltage and current wave forms entering or exiting a device under test(DUT), this sampling process typically occurs every 0.5us to 1us depending upon the analyzer model being used, some lower specification models from other manufacturers may sample as low as 100ks/s. Once sampled, the data is processed by a dedicated high speed digital signal processor (which can also be implemented on modern FPGAs) and the various derived parameters are calculated.

One important difference between oscilloscopes/data acquisition cards and true power analyzers is that a high end power analyzer (such as an N4L PPA) is able to record, store, process and delete samples “on the fly”. This means there is never a gap in the sampling process as the memory buffer is continually emptied after the samples are processed . This is uncommon and yet absolutely necessary for accurate power measurements.

N4L’s High Precision Power Measurement Signal Chain

N4L’s High Precision Signal Chain

N4L Power Analyzers are able to transfer raw sample points at full resolution across the isolation barrier. Traditional power analyzers do not transfer this “high speed” data as the isolation stage represents a bottleneck, other analyzers therefore perform computations prior to data transfer to the main CPU card.

The benefit of transferring raw data samples across the isolation barrier means that the FPGA and DSP can perform inter-phase parallel signal processing across phases. The result is exceptional phase accuracy through the implementation of a real time DFT performed upon the raw data samples. The nominal phase accuracy of the PPA5500-TE is 0.003º. A dedicated frequency detection DSP continuously tracks the input frequency and is capable of parallel filtering the input signal. This is beneficial if PWM type wave forms are to be analyzed, in all cases the parallel filtering process does not affect the raw data used to calculate the measured parameters, it only applies a filters to the data used for frequency detection.

What makes N4L power analyzers different to our competitors?

There are many power analyzer options on the market offering varying degrees of accuracy, yet at the top end of metrology you can narrow down your options to only a handful of manufacturers. Each manufacturer will profess that their solution is the best for one reason or another, at N4L we refer to hard facts and traceable data giving our customers clear, concise and useful metrics to make a decision. We have also developed various application modes and sophisticated power measurement algorithms that are key to achieving accurate measurements within dynamically changing environments. It is worth noting that it is a lot easier to achieve accurate measurements within a calibration environment using sinusoidal reference wave forms than it is within a distorted, dynamically changing motor drive or LED power measurement application for example. With this in mind N4L, alongside Oxford University (UK) have developed a 2MHz ISO17025 accredited watts calibrator based upon calorimetric principles utilizing a unique liquid heat transfer medium to enable rapid calibration of a test device. This research has given us a world leading watts reference up to 2MHz in frequency and highlights our philosophy of designing products that perform as well in real applications as they do on a calibration rig. The industry obsession with headline specifications often results in instrument designers neglecting what really matters – accurate measurements within real world environments in the presence of distorted wave forms and wide band power.

Key reasons to choose N4L:

Best high frequency performance on market – key to achieving accurate power measurements of devices containing high distortion/switching frequencies

Example Applications

Variable speed motor drives have become the go to technology for motor control in many industries. From industrial automation, utility waste movement, large scale traction drives and now the electrical vehicle market. In particular, variable speed inverter drives pose great challenges to a power analyzer with regards to accurate power measurements and the PPA3500, PPA4500 and PPA5500 have been designed with this in mind.

N4L PPA series power analyzers offer a highly accurate solution to standby power analysis, with custom designed software providing the user with the ability to make quick, simple, compliant measurements with ease. Each N4L Power Analyzer is supplied with UKAS ISO17025 accreditation, providing the user with ultimate confidence that the measurement made is correct and traceable.

The PPA55x1(fully compliant) and PPA5530(pre-compliant) offer IEC61000-3-3, IEC61000-3-2, IEC61000-3-11 and IEC61000-3-12 compliance testing against the latest standards. N4L have developed a comprehensive ISO17025 calibration protocol that is available upon request to cover all aspects of IEC61000 harmonics and flicker. In particular, the d(t) tests performed as part of N4L’s IEC61000 ISO17025(UKAS) calibration protocol are unique to the industry as it is extremely uncommon to find coverage of d(t) tests within an accredited calibration procedure.

The N4L PPA5500-TE has been developed specifically for the transformer test and development industry, featuring 0.02% reading + 0.02% range error the PPA5500-TE is a market leader and reference for the transformer test sector. One of the key design features that give the PPA5500-TE’s such a performance advantage is its current shunt design, this proprietary design enables the PPA5500-TE to achieve 0.003deg phase accuracy. No other power analyzer on the market performs as well in this area, which is a key performance parameter for measurement at low power factors – for example during off-load core loss analysis.

The PPA4500 and PPA5500 feature market leading phase accuracy, as such they are well suited to inductor(choke) loss analysis at both low and high frequencies. Typical power factors during inductor loss analysis are very low, as such great demand is placed upon accurate measurement of the phase shift between voltage and current in order to calculate the correct watts dissipation of the inductor or choke.

Evaluation of solar inverter systems require an instrument to synchronize to both DC waveforms (output of the solar cell) as well as AC waveforms (output of the inverter). This means the analyzer needs at least two independent frequency measurement channels, all PPA’s are capable of such measurements. In addition to this, it is vitally important for the power analyzer to acquire data from each channel synchronously. This ensures that power measurements and subsequent efficiency measurements are made using data that occurs during the same window in time, it is very common for power analyzers to not acquire data synchronously from each channel which leads to incorrect efficiency measurements. All N4L power analyzers can also be used for harmonic analysis of the inverter output waveform in order to verify compliance to relevant standards.

Calibration and Warranty

N4L have developed unique power analyzer calibration rigs in order to provide calibration throughout the entire frequency range of the instruments we supply. This has resulted in calibration procedures which would not be possible when utilizing off the shelf commercially available calibrators. Using traceable calibration equipment combined with N4L proprietary signal generation equipment, every power analyzer is supplied with a comprehensive calibration certificate. Our UKAS 17025 laboratory scope accompanies our high frequency calibration test rigs (utilizing traceable calibration instrumentation) providing total coverage of our power analyzer bandwidth. During 2016, N4L became the first power calibration laboratory to be ISO17025 accredited for calorimetric power calibration up to 2MHz with an uncertainty of <0.3%. This technology has been utilized to validate the design of all N4L Power Analyzers across their entire frequency range with exceptional accuracy.

All N4L power analyzers are supplied with a 3 year warranty, software is free to download from our website and firmware upgrades are also free of charge. Please see our tutorial series which covers an array of applications, including PWM motor drive analysis, AC/DC converters and standby power. To obtain more information on any of our power analyzers, please do not hesitate to contact us

Why not check out our AC Power Sources, these are available from 3kVA up to 67kVA in both single and three phase configuration. Our Programmable AC Power Sources are capable of arbitrary waveform generation and half cycle sequencing events, harmonic and inter-harmonic generation as well as a full signal bandwidth of 1kHz (Small signal 15kHz).

Products in this series

PPA5500-TE Transformer Edition

The PPA5500-TE is a specialized Transformer Power Analyzer, compliant to IEC60076-8 and featuring 0.003deg phase accuracy – certified to ISO17025.